I have a Early 2008 24" iMac. I'm looking to trade it in on a new 27". I'm wondering what cable I will need and adaptor, if necessary, to migrate my stuff from the old computer to the new. Looks like I have USB 2.0 and Firewire 400/800 on the 2008 iMac. Will a thunderbolt cable + a firewire adaptor work? Thanks! Edit: I also have an external USB HD that I use for Time Machine backup. I suppose I could plug that into my new iMac for Migration Assistant?